Fucking. Yes. I won't get into the details very much because she could still be out there...searching...but I was majorly stalked on Twitter once. It came to the point where I had to just protect my account. Since a protected account seems counterintuitive to what Twitter is supposed to be like, I didn't see a point in using it any more. Haven't used Twitter since, haha. So maybe that's the closest experience I have that can compare to yours. But that was a rare, probably (HOPEFULLY) a once-in-a-lifetime scenario. Women online have to deal with that shit every day. I think this XKCD sums it up well:
Twitter definitely needs better block mechanisms, while we're at it.
I am lucky in that I haven't had any seeming stalkers or potential bad situations on the internet, at all, so far. Of course it does strike me as a numbers game so it's quite possible, one day. I've read horror stories about other women's experiences for sure. I am sure your experience made you more wary about your interactions online. I am glad that it did not drive you off. I do advocate different usernames for different websites when possible/reasonable, though. Not sure how many other people do this. Sometimes it seems people have one handle for everything. I prefer to compartmentalize.